As shown in FIG. 1, a bicycle tread rod 30 of the prior art is fastened with a front fork 10 of the bicycle and is intended for use in allowing a person to step on it for performing an acrobatic feat.The front fork 10 is provided at the lower end thereof with a horizontal threaded tube 20 having an inner threaded hole 201.The tread rod 30 is provided with an outer threaded portion 301 which is engaged with the inner threaded hole 201.
Such a tread rod of the prior art as described above is defective in design in that the outer threaded portion 301 of the tread rod 30 is vulnerable to damage or even severance caused by the stress that is concentrated at the portion indicated by an arrow "A" at such time when a person steps on the tread rod 30.In addition,it is rather difficult to take the severed outer threaded portion 301 out of the inner threaded hole 201.